Power saw for cutting plaster casts



May 7, 1946. F. HOOD ETAL POWER SAW FOR CUTTING PLASTER CASTS Filed June 19, 1944 II ll J F an:

INVENTORS FRANK E. H000.

HOOD.

BY E i M Afro/wk).

Patented May 7, 1946 POWER SAW FOR CUTTING PLAsTEa oAs'rs Frank E. Hood and James Edgar Hood,

, LongBeach, Calii'.

Application June19, 1944, Serial No. 541,024 6 Claims. (01. 3o 124) The present invention relates to improvements in power saws for cutting plaster casts, and its principal object is to provide. a. saw of the char.- acter described whereby a cast applied to a patient may be cut speedily for removal without. any danger of. injuring the skin of. the patient.

A further object of the invention is to provide,

in combination with a saw of the character described, a protecting foot adapted to ride between the skin, of the patient and the cast so as to prevent the saw from coming, in contact with the skin of the patient.

It is further proposed to provide an adjustable depth gaugefor the saw whereby the saws cutting action may be limited exactly to the thickness of the cast to be out.

It; is further proposed to provide means for carrying oil the saw dust and to arrange the same in front of the saw immediately above th cast,

and to make the same adjustable With the depth gauge.

And finally, we propose to provide a saw of the character described that is well balanced, easy to operate, quickly adjusted, and economic to manufacture.

Further objects and advantages of our invention will appear as the specification proceeds, and the novel features of our saw will be fully delined in the claims hereto appended.

The preferred form of our invention is illustrated in the accompanying drawing, in which:

Figure 1 shows a top plan view of our power saw;

Figure 2, an end view of the same; and

Figure 3, a fragmentary plan view of the end portion of the power saw with certain parts re-- moved.

While we have shown only the preferred form of our invention, we wish to have it understood that various changes or modifications may be made within the scope of the claims hereto attached without departing from the spirit of the invention.

Referring to the drawing in detail, our power saw I comprises, in its principal features, a motor 2, a motor shaft 3 having a rotary saw 4 at one end and a fan 5 at the other end, a foot 6 underneath the saw, a depth gauge 1 adjacent the say, a discharge conduit 8 for the dust, and a handle 9 whereby the whole device may be manipulated.

The motor housing has a tapered extension Ill coming to within close proximity of the saw and serving to furnish a bearing for the motor shaft near the saw. It also has a rectangular frame II projecting therefrom in the direction of the saw and above the axis thereof, the frame comprising .long'itudinallbars l2 and I3 and two crossmembers l4 and 15 disposed on opposite sides of the saw.

The. frame H supports. a hood it over the saw. It has a lateral extension ll, substantially in the plane of the saw, and this extension carries, with freedom of vertical adjustment, as by the screw and slot arrangement, shown at l 8, a leg I9, which is curved toward the saw so as to support the foot 5 underneath the saw.

The foot-t protects the skin of the patient for longitudinal cuts, but may be removed for vertical cuts into the plaster, when it is desired to out a. window into the cast. The adjustment takes care of saws of different sizes.

The front frame member M, which is widened in its central portion, as at 20, carries the depth gauge 'i made in the form of a rectangular frame 2| having two vertical columns 22 slidable in the member M, a top bar 23 and a bottom shoe 24 adaptable to ride on the plaster. The gauge may be adjusted by means of a screw 25 revolvably anchored in the frame member l4 and threaded into the top bar 23.

The discharge tube 8 for the saw dust is arranged alongside of the motor housing and has a front elbow 2B leaning toward the lower edge of the saw so as to receive the saw dust. It is formed with a cut-out 21 in the edge facing the saw to provide better access for the saw dust. The front elbow is supported by an extension 28 of the gauge shoe 24 so as to be adjustable therewith.

The rear end of the discharge conduit connects, through an elbow 30, to the central intake 3| of a housing 32 for the fan 5. The tangential outlet 33 has a suitable dust receiving bag 34 secured thereto.

The elbow 30 is revolvable in the intake 3|, as at 35 to allow of adjustment of the front end of the conduit by the raising and lowering of the gauge shoe 24, and the conduit 8 is extensible, as at 36, to allow of slight changes in the length of the conduit incident to the adjustment.

The frame I I has a bracket 38 rising therefrom between the saw and the motor housing, and the rear member 39 of the bracket carries the handle 9 which is preferably made in the form of a standard hand-saw handle. The handle may be equipped with a trigger 4| for opening and closing the motor circuit and with a locking pin 42 for locking the trigger in circuit-closing position.

Suitable electrical connections have been indicated at 43 and 44, but need no description since they are of conventional character.

In use, the operator suitably adjust the foot 6 and the gauge 1, which latter adjustment also places the front end of the conduit 8 into the proper position. The operator then lifts the device, gripping the handle with his right hand and the fan housing with his left hand, introduces the foot 6 underneath the plaster cast, pulls the trigger 4| for starting the motor and presses forward.

The saw will now out through the plaster and the fabric of the cast, such as cloth, cotton or woolen padding, without any danger of injuring the skin of the patient.

The dust will be sucked into the conduit due to the action of the fan and will be discharged into the bag 34.

We claim:

1. A power saw for cutting plaster casts comprising a motor having a shaft projecting therefrom, a rotary saw on said shaft being spaced from the motor, a fixed member secured upon the motor and extending to within close proximity of the saw, and a gauge carried by the end of the fixed member adjacent the saw to limit the cutting depth of the latter, the gauge comprising a frame slidable in the fixed member and having a shoe adapted to ride on the surface of the cast to be out, and threaded means for vertically adjusting the frame with respect to the fixed member.

2. A power saw for cutting plaster casts comprising a motor having a shaft projecting therefrom, a rotary saw mounted for operation by the shaft, 2. fixed member secured upon the motor and extending to within close proximity of the saw, a, gauge carried by the fixed member for limiting the depth of the cut, and a discharge tube for catching the saw dust, the discharge tube having one end supported by the gauge.

3. A power saw for cutting plaster casts comprising a motor having a shaft projecting therefrom, a rotary saw mounted for operation by the shaft, a fixed member secured upon the motor and extending to within close proximity of the saw, a gauge, adjustable means on the fixed member for supporting the gauge, and a discharge tube for catching the saw dust, the discharge tube having one end supported by the gauge so as to be adjustable therewith.

4. A power saw for cutting plaster casts comprising a, motor having a shaft projecting therefrom in opposite directions, a rotary saw on one end of the shaft, a fan on the other end of the shaft having a housing surrounding the same, a depth gauge for the saw, means for adiustably supporting the same, and a discharge conduit arranged alongside the housing, the discharge conduit having one end supported by the depth gauge in operative proximity to the saw for catching the saw dust so as to be adjustable with the gauge, and having its other end connected to the fan housing.

5. In a power saw for cutting plaster casts, a motor having a shaft projecting therefrom, a rotary saw mounted for operation by the shaft, an adjustable depth gauge for the saw, and a discharge conduit for the saw dust having its receiving end supported by the depth gauge so as to be adjustable therewith.

6. A power saw for cutting plaster casts comprising a motor having a shaft projecting therefrom, a rotary saw mounted for operation by the shaft, a fixed member secured upon the motor and extending to within close proximity of the saw, and a gauge carried by the fixed member adjacent the saw to limit the cutting depth of the latter, the gauge comprising a frame slidable in the fixed member and having a shoe adapted to ride on the surface of the cast to be cut, and means for vertically adjusting the frame with respect to the fixed member.

FRANK E. HOOD.

JAMES EDGAR HOOD. 

